It seems to be a site much like
Worth1000.Lots of unusual graphics to be found there!
Warning: Some graphics might be...um...graphic!! :D
Been to Worth1000. Theirs often bear their logo but I would not be surprised to find some there.
I had mine filed under Art:OptIllusion. Searched "Optical illusion images online and many came up with a similar style and not necessarily the same artist (varied styles).
Could be another crossover art style.